Automatically-adjustable drawing-pen.



PATENTED MAY 29, 1906.

J. A. MARTIN-000KB. AUTOMATICALLY ADJUSTABLE DRAWING PEN.

APPLICATION FILED MAY 6, 1905.

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UNITED sTATEs PATENT OFFICE.

Specification of Letters Patent.

Patented May 29, 1906.

Application filed May 6,1905- Serial No. 259,168.

To alt whom 7225 may concern.-

Be it known that I, JOHN ALFRED MARTIN- COO'KE, a citizen of the United States, residing at Louisville, in the county of Jefferson and State of Kentucky, have invented a new and useful Automatically-Adjustable Drawing-Pen, of which the following is a specification.

This invention relates to improvements in drawing-pens for draftsmen and the objects of my invention are to provide a drawing-pen with which the heaviness of the lines may be regulated without manipulating a screw and a line comprising portions of different heaviness may be drawn at a single sweep of the pen, simplicity of construction, durability, and cheapness of manufacture. These objects I attain by means of the mechanism illustrated in the accompanying drawings, in which Figure 1 is a side elevation, and Fig. 2 an edge elevation.

Similar reference-numerals refer to similar parts throughout both views of the drawings.

The drawing-pen 1 is of the usual form,

I with the point slightly curved in the direction of motion. The sides or blades 2 of the pen proper are so constructed that they normally press together at the point, and their spread is regulated by means of the thumbscrew 3 which is threaded in one of the blades 2 and presses at its end against the inner side of the corresponding blade. The thread on the stem of screw 3 is cut away for a suitable distance from the end, and upon the smooth portion thus formed is clamped an arm 4 by means of a thumb-screw 5, which passes through the upper end of the arm. The lower end of the arm is forked, and in the fork thus formed is. journaled the wheel or roller 6. A light spring 7 or some equivalent means connects the upper end of arm 4 with the upper part of the pen in such a manner that roller 6 remains normally in the position shown in the figures. Roller 6 cannot fall below this position on account of the head of screw 5 pressing against the edges of blades 2. The operation of the pen will now be understood.

The set-screw 5 maybe released sufficiently to allow set-screw 3 to be turned with the hand, and by this means the point of the pen may be adjusted so as to draw the lightest line required when roller 6 is not in use or not pressing against the pa er. Set-screw 5 1s then screwed up in or er to clamp arm 4 tightly on the stem of screw 3. The pen is held in the hand in such a position that wheel 6 is on the advancing side. When it is desired to increase the heaviness of the line,

the handle of the pen is leaned forward, thus causing the wheel 6 to press upon the paper and turning screw 3, so that the blades 2 of the pen are spread. It is obvious that the more the handle 1 is leaned forward the more the blades will be spread and the heavier will be the line made thereby. When it is desired to decrease the heaviness of the line, it is only necessary to bring the handle 1 more toward the vertical position, when spring 7 acts to keep the roller 6 upon the paper, screw 3 is unscrewed, and blades 2 allowed to approach each other.

Having thus described my invention so that any one skilled in the art pertaining thereto may make and use it, what I claim as new, and desire to secure by Letters Patent,

1. In a drawing-pen, the combination of a pen and means adapted to work in contact with the paper or ot er stationary surface in the plane of the paper for automatically spreading the blades of said pen while a line is being drawn. v

2. In a drawing-pen, the combination of blades, means for setting the normal spread of said blades, and means adapted to work in contact with the pa er or other, stationary surface in the plane 0 the paper for automatically spreading said blades while drawing a 3. In a drawing-pen, the combination of blades, a set-screw for regulating the normal spread of said blades and an arm clamped on said set-screw and adapted to work with its free end in contact with the paper or other surface in the plane of the paper and regulate the spread of said blades.

JOHN ALFRED MARTIN-COOKIE. Witnesses:

' ABRAHAM KNOBEL,

W. H. BEYWROTH. 

